1. Field
One embodiment of the invention relates to a semiconductor chip mounting body, a method of manufacturing the semiconductor chip mounting body and an electronic device.
2. Description of the Related Art
Recently, semiconductor chip mounting bodies, which are mounted through face-down methods such as ball grid array (BGA) or chip scale package (CSP), are known. The face-down method is carried out by connecting electrodes of semiconductor chips to circuit patterns of circuit boards via solder bumps. The advantage of the mounting technique by face-down method is that the mounting area occupied can be made small. However, in the mounting technique by face-down method, there is a risk that the bonding part (solder) will be destroyed due to the stress brought about by the difference between the thermal expansion coefficients of the circuit board (e.g. glass epoxy resin) and of the chip (silicon).
Based on the above condition, a technique for filling a thermosetting resin solution between the circuit board and the semiconductor chip after the face-down mounting process of connecting electrodes of the semiconductor chip to the circuit pattern of the circuit board via solder bumps, and for forming a hard bonding member is attempted. By fixing the semiconductor chip on the circuit board, the reliability of the connection between the circuit board and the semiconductor chip, with regards to thermal stress caused by processes like heat cycle, is enhanced.
On the other hand, Jpn. Pat. Appln. KOKAI Publication 2000-294601 discloses a mounting body of a semiconductor device wherein a sealing material is filled between the circuit board and the semiconductor chip. This sealing material contains thermosetting resin and filler (e.g. silica filler), whose dielectric constant is smaller than that of the thermosetting resin. The silica filler is disposed in a portion of the sealing material that lies on the circuit board side. The mounting body can be used to reduce crosstalk between interconnections. Further, in Jpn. Pat. Appln. KOKAI Publication 2000-294601, it is disclosed that a filler previously containing a magnetic material is included in a resin composition, for example, metal powder coated with Teflon (registered trademark). In the above document, it is disclosed that the above composition is supplied between the circuit board and the semiconductor device and the filler in the resin composition structure is set on an interface with respect to the circuit board or on an interface with respect to the semiconductor device by utilizing the pulling the filler through the use of a magnet.